Musannaf Ibn Abi Shayba 3:441

Abu Bakr narrated to us, he said: Waki’ narrated to us, from Sufyan, from Jabalah ibn Suhaym, he said: I asked Ibn ‘Umar about the prayer of the sick person upon a staff. He said: "I do not command you to take idols besides Allah. If you are able to pray standing, then do so; and if not, then sitting; and if not, then lying on your side."